In many cases, Office 365, Office 2016, and Office 2013 activate automatically after you install Office on your PC, and you won't have to manually activate Office or enter a product key. But sometimes Office needs your help to activate.

If you're prompted to activate, scroll down and select your Office product below. If you access this topic from the Activation wizard, you can see your Office product in the wizard, like this:

Office Home and Student, Office Home and Business, Office Professional, or individual Office applications

Do you have a product key? It's ok if you don't--not every version of Office comes with a product key. It depends on how you got your copy of Office. If you have a product key, see Where to enter your Office product key. After you enter your product key (if you have one), see install Office. After you install Office, it should automatically activate for you. If it doesn't, you can follow the steps in this article.

If your Office product key doesn’t work, or has stopped working, you should contact the seller and request a refund. If you bought a product key separate from the software, it’s very possible the product key was stolen or otherwise fraudulently obtained, and subsequently blocked for use. Unfortunately, there are many dishonest sellers who offer stolen, abused, or otherwise unauthorized Microsoft product keys for sale. Sometimes these product keys are printed on counterfeit labels or cards with a download link to Microsoft software, and sometimes they’re distributed with software media that is unauthorized for resale, such as promotional media, original equipment manufacturer reinstallation media, or other Microsoft program-specific media.

For a one-time purchase of Office 2016 or Office 2013, you can install Office on only one computer. If you try to install and activate Office on a different computer (owned by you or someone else), or on the same computer after a hardware change, you might see an error message that you have reached the maximum number of activations.

If you follow the transfer terms in the Software License Terms, you can move Office to a different computer, but you must activate it by phone and then uninstall Office from the original computer.

Do you have a product key? It's ok if you don't--not every version of Office comes with a product key. It depends on how you got your copy of Office. If you have a product key, see Where to enter your Office product key. After you enter your product key (if you have one), see install Office. After you install Office, it should automatically activate for you. If it doesn't, you can follow the steps in this article.

If your Office product key doesn’t work, or has stopped working, you should contact the seller and request a refund. If you bought a product key separate from the software, it’s very possible the product key was stolen or otherwise fraudulently obtained, and subsequently blocked for use. Unfortunately, there are many dishonest sellers who offer stolen, abused, or otherwise unauthorized Microsoft product keys for sale. Sometimes these product keys are printed on counterfeit labels or cards with a download link to Microsoft software, and sometimes they’re distributed with software media that is unauthorized for resale, such as promotional media, original equipment manufacturer reinstallation media, or other Microsoft program-specific media.

If Office prompts you to activate by entering an email address, it's important to enter the Microsoft account that's associated with your Office 365 Home, Personal, or University subscription. If sign-in fails, you might be entering the wrong email address. For help identifying the correct email address to use, see I can't remember the Microsoft account or password I use with Office

In most cases, you won’t need a product key for your Office 365 for business subscription. For example, if you bought Office 365 online directly from Office.com or the Microsoft Store, you can sign in and set up Office 365 for your organization without entering a product key.

If you do have an Office 365 for business product key, you can use it to activate a new subscription, renew a subscription, or add licenses to a subscription. See Enter your product key for Office 365 for business to enter your product key (if you have one). Then you can install Office. After you install Office, it should automatically activate for you. If it doesn't, you can follow the steps in this article.

If your Office product key doesn’t work, or has stopped working, you should contact the seller and request a refund. If you bought a product key separate from the software, it’s very possible the product key was stolen or otherwise fraudulently obtained, and subsequently blocked for use. Unfortunately, there are many dishonest sellers who offer stolen, abused, or otherwise unauthorized Microsoft product keys for sale. Sometimes these product keys are printed on counterfeit labels or cards with a download link to Microsoft software, and sometimes they’re distributed with software media that is unauthorized for resale, such as promotional media, original equipment manufacturer reinstallation media, or other Microsoft program-specific media.

If Office prompts you to activate by entering an email address, it's important to enter the work or school account that you used to install Office 365 for business. If sign-in fails, you might be entering the wrong email address. For help identifying the correct email address to use, see I can't remember the Microsoft account or password I use with Office.

If your Office product key doesn’t work, or has stopped working, you should contact the seller and request a refund. If you bought a product key separate from the software, it’s very possible the product key was stolen or otherwise fraudulently obtained, and subsequently blocked for use. Unfortunately, there are many dishonest sellers who offer stolen, abused, or otherwise unauthorized Microsoft product keys for sale. Sometimes these product keys are printed on counterfeit labels or cards with a download link to Microsoft software, and sometimes they’re distributed with software media that is unauthorized for resale, such as promotional media, original equipment manufacturer reinstallation media, or other Microsoft program-specific media.